You're cherry-picking to establish your conclusion. Lots of classic authors from that period (George Eliot for example) didn't serialise their works in magazin

You're cherry-picking to establish your conclusion. Lots of classic authors from that period (George Eliot for example) didn't serialise their works in magazines. Also the 19th century is not by any means considered generally superior to any other period in English literary history. Eg Jane Austen and Virginia Woolf and James Joyce are looking sternly in your direction from either side of that timeline for example.